tags 268495 patch
user ubuntu-de...@lists.ubuntu.com
usertags 268495 ubuntu-patch jaunty
thanks
On Thu, Oct 28, 2004 at 08:28:20PM +0100, Colin Watson wrote:
> It's still possible to hang parted_server by entering an empty name,
> which is a separate problem: the implementation of the SET_NAME command
> uses fscanf(" %a[^\n]"), which never returns if you only send
> whitespace.
Here's a patch which I think fixes this. I've only tested this in a test
harness, not yet in a full installation, but I think it's right.
--
Colin Watson [cjwat...@ubuntu.com]
Index: parted_server.c
===================================================================
--- parted_server.c (revision 56922)
+++ parted_server.c (working copy)
@@ -118,7 +118,38 @@
the function `scanf' */
#define iscanf(...) fscanf(infifo,__VA_ARGS__)
+/* Read the remainder of this line from the input FIFO, skipping leading
+ * whitespace. Sets *str to NULL if there was no data left in the FIFO (as
+ * opposed to merely optional leading whitespace followed by a newline,
+ * indicating an empty argument following the whitespace; in that case, set
+ * *str to the empty string). Caller is expected to free *str.
+ */
void
+iscan_line(char **str)
+{
+ int c;
+
+ *str = NULL;
+
+ c = fgetc(infifo);
+ if (c == EOF)
+ return;
+ while (c != EOF && c != '\n') {
+ if (isspace((unsigned char) c))
+ c = fgetc(infifo);
+ else {
+ ungetc(c, infifo);
+ break;
+ }
+ }
+
+ if (c == EOF || c == '\n')
+ *str = calloc(1, 1);
+ else
+ iscanf("%a[^\n]", str);
+}
+
+void
synchronise_with_client()
{
char *str;
@@ -287,7 +318,8 @@
oprintf("\n");
if (timer_was_started)
start_timer();
- if (1 != iscanf(" %a[^\n]", &str))
+ iscan_line(&str);
+ if (!str)
critical_error("No data in infifo.");
if (!strcmp(str, "unhandled")) {
log("User canceled exception handler");
@@ -1471,7 +1503,8 @@
for (flag = first; flag <= last; flag++)
states[flag - first] = false;
while (1) {
- if (1 != iscanf(" %a[^\n]", &str))
+ iscan_line(&str);
+ if (!str)
critical_error("No data in infifo!");
if (!strcmp(str, "NO_MORE"))
break;
@@ -1530,7 +1563,8 @@
if (part == NULL || !ped_partition_is_active(part))
critical_error("No such active partition: %s", id);
log("Partition found (%s)", id);
- if (1 != iscanf(" %a[^\n]", &name))
+ iscan_line(&name);
+ if (!name)
critical_error("No data in infifo!");
log("Changing name to %s", name);
open_out();
